Tooth brush



June 9, 1936. J. A. MALCOLM 2,043,898

TOOTH BRUSH Filed May 4, 1935 2 Sheets-Sheet 1 June 9, 1936. I A g2,043,898

TOOTH BRUSH Filed May 4, 19:55 2 Sheets-Sheet 2 stock or back;

Cal

Patented June 9, 1936 PATENT OFFICE TOOTH BRUSH James A. Malcolm,sheraden, Pa.

Application May 4', 1935, Serial No. 19,892

8 Claims. (01. 15-167) This invention relates to improvements in toothbrushes, or more particularly to improvements 'in the form andconstruction of tufts of bristles in a brush, which improvements renderit highly efficient in the cleansing of teeth of all known structures.

It has long been a desiresto construct a brush that will reach andcleanse any surface of any tooth that may be found in any mouth whethernormal or abnormal in form, position or relation to adjacent teeth, andwhich brush will cleanse teeth with the least amount of effort. This isaccomplished to a remarkably high degree with the product of the presentinvention.

In past forms of tooth brushes, one or moresets or tufts of bristleshave been found to interfere with other tufts or with each other ingetting into deep embrasures. The interfering tufts are displaced froman interfering position only with considerable difllculty, as byexerting great pressure. In their displaced positions, the bristles aregenerally found to be improperly placed for efllcient cleaning. Thebrush to be described below, as a product of the present invention, isso constructed as to avoid any objectionable interference of tufts withother tufts in the brush during a. mouth-cleansing operation.

In the accompanying drawings, which serve to illustrate the presentinvention, and in' which like reference characters denote like parts,

Fig. 1 is a view of the under side of the brush Fig.2 is a plan view ofthe brush;

Fig. 3 isa side elevation of the brush head;

Fig. 4 is a view of the free end of the brush head;

Fig. 5 is a longitudinal section of the brush head on line 5-5 in Fig. 2in the direction of the arrows;

Figs. 6 and '7 are transverse sections of the brush head on line 6-6 and'l-"l, respectively, in Fig. 2 in the direction of the arrows;

Fig. 8 is a side elevationof a modified brush head; and

Figs. 9 and 10 illustrate the manner in which certain portions of thebrush perform their cleaning action on teeth.

Referring to the drawings, the tooth brush shown comprises a handle Iand a brush head 2 provided with tufts forming a bristle face havingcontours of the type to be described. The tufts 7 are set in sockets 3in the usual manner. Although only one arrangement of sockets is shown Jin Fig. 1, it is to be understood that this arrangement may be varied,depending on the size of the'brush head and the number of tufts in thebrush head.

Oneimportant feature of the brush is a concavity or a cuppedportion,which might also be described as a scoop-like or spoon-like portion,formed by tufts adjacent the free end of the brush head, substantiallyas illustrated in Figures 2 to 7, inclusive. A ridge is formed on theborder of the cupped portion by long bristles intufts 4, 5, 6, I, 8, 9,and Ill. The free ends of the bristles forming the ridge are illustratedby the darker dots in Fig. 2. The lighter dots indicate the approximatepositions of the ends of the shorter bristles. The ridge may be in theform of an oval or. an ellipse or in approximately such forms.

Another feature of importance is the portion of the ridge extendingtransversely of the brush head and formed by bristles near the free endof the brush ,head. This portion of the ridge is preferably in the forma curve; the curve being convex toward the free end of the brush head.

The advantage of this will be explained below.

The ridge may extend from the ends of said curve. straight or in curvedform, along both sides of the brush and part of the way'toward thehandle end of the brush head. The top of the ridge perferably has agreater width than that formed by the thickness of a single line ofbristles. That is, the top of the ridge may be several or more bristlesacross. Bristles on both sides of the ridge are of decreasing length ina direction away from the ridge.

A high portion in the ridge is formed by bristles in tufts 4, 5, and 8.Portions of the ridge formed 'by bristles in tufts 5, 6, and I on oneside of the brush and by bristles in tufts 8, 9, andlll on the otherside of the brush, slope toward the base of the brush, reaching its lowportions at about tufts 1 and Ill, respectively.

Bristles, in tufts 4, I 4, and I5 within the ridge, are of decreasinglength toward the handle I, the slope formed thereby reaching its lowportion at tufts l5 and I6 beyond which the bristles increase in lengthto tuft I 3 which is approximately at the end of the concavity formedwithin the ridge, as shown inrFig. 5.

A slope is formed in the bristle face by bristles of decreasing lengthin tufts 4 and I1 from the high portion of the ridge to the free end ofthe brush head. As shown in Fig. 4, the portion of the ridgenearest thefree end of the brush head and formed by bristles in tuft 4 and some ofthe bristles in tufts 5 and 8, extends transversely of the brush headand is substantially parallel with the base. The outer bristles in tuftsI and I, as well as in the other tufts extending along the sides of thebrush, are of decreasing length towards the sides of the brush, therebyforming a bevel on each side of the bristle face throughout the lengthof the brush head.

The tufts in the brush head toward the handle and away from the regionof the concavity may be of any desired number and may be of thecharacter shownin Figs. 2, 3, and 5 or of the character showninFig.8.Intheformertypeofb ,the.

rear tufts are shown as of increasing length toward the handle. 1n thebrush of the latter type (Fig. 8) the rear tufts may form more or lessof a convexity. The transverse rows of tufts in the rear portion ofeither type of brush are tapered so as to form transverse ridgesextending I from bristles in the center of the tufts on one side of thebrush to bristles in the center of the tuftslon the other side.

It is seen from the above description that the cupped or concave portionin the bristle face of of the ridge to reach into the groove formed 'atthe gun line around the entire rear side of the tooth. At the same time,due to the concavity inthebrush,theendsofthebristles areincontactwiththe upper rear part of thetooth. A slight pressure brings the endsof the bristles forming the sldes of the concavity and positionedtowards the sides-of thrbrush head into embrasures on either side of thetooth and in contact withthesidesurfacesofthetoothasshownby the dottedlines in Fig. 10. Furthermore, while cleaning the rear of one tooth, theteeth on either a side are being cleaned on their adjacent surfaces bytheends of bristles in the bevelled portions of the brush head outsidethe ridge described above. It is important to note that the bristlesreaching into the enibrasures contact the surfaces of the sides of thetooth with their ends and not with their sides. Very little cleaningaction results from rubbing of sides of bristles against atooth. Toobtain the best results, the ends of the bristles must rub across thesurface to be cleaned.

In Fig. 9 there is illustrated the condition of the brush in its normalposition, and its condition when cleaning on the inner side of bridgework. The ends of the outer tufts are brought together over the innertuft by the sides of the groove formed by the bridge and the gum. The'shorter inner tuft and thebevelled sides'of the bristle face formed byouter tutti make it possible'fortheendsofthebristlesintheside'tuftstoreach with ease the entire surfaceof the groove.

It has been found that abrush having-the features described maka itpossible to clean teeth thoroughly to the gum line. The brush readilyreaches into grooves andsulci in anindividual tooth and'in'to embrasures(labial. buccal and lingual) formed by the relative positionof one,

'tooth with respect to another or the relative poaitionof a tooth withrespect to its investing What I claim is:-

1. Atoothbrush havingbristlesformingin the bristle face a ridge that issubstantially in the form of an ellipse having its major axis extendinglongitudinally of the brush head. and from 5 substantially the outerwall of bristles t the free end of the brush head, and bristles plinwardly and outwardly from the ridgeand of decreasing length-away fromthe ridge.

2. A tooth brush having bristles forming in the 10 bristle face a ridgethat is substantially inthe form of an ellipse having its major axisextending longitudinally of the brush head, and from sub stantially theouter wall of bristles at the free end of the brush head, a portion ofthe plane of the 1 ridge near the free end of the brush head slopingtoward the base of the brush head in the direc-- tion of the handle.

3. A tooth brush having bristles forming in the bristle face a ridgethat is substantially in the form 20 of an ellipse having its maioraxisextending longitudinall of the brush head and from substantially the'uter wall of bristles at the free end of the brush head, a portion ofthe plane of the ridge near the free end of the brush head slopinglac-'2 ward the base of the brush head in the direction of the. handle,and bristles placed inwardly and outwardly from the ridge and decreasingin length in directions away from the ridge.

4. Inatoothbrushhavingapluralityoftufts 30 forming a-brlstle face. asubstantially curved U-' shaped ridge formed by the ends of bristles inthe said bristle face, the said ridge extending cross-wise of thebristle face adjacent the free end of the brush head and the said ridgehaving its convex portion toward the said free end of the brush head.

5. In a-tooth brush having a plurality of tufts forming a bristle face,a substantially curved U- shaped ridge formed by the ends of bristles inthe 40 said bristle face, the said ridge extending crosswise of thebristle face adjacent the free end of the brush head and the said ridgehaving its convex portion toward the said free end of the brush head,and other bristles on both sides ofthe said 4 ridge. 1 p 8. A toothbrush having bristles forming a ridge in the bristle face, the saidridge extending trans-'- versely of the bristle face and along oppositesides "thereof, .portions of the said ridge on opposite 5 sides of thebristle face lyingin a plane that slopes toward thebaseofthebrushheadinthedirection of the handle, the said ridge extending fromthe free end of the brush head, and the said portionsoftheridgeinthesaidplanebeingadjacentthe said free end. i

I '1. A'thoth bnish'having'bristles forming a ridge in the bristle face,the-said ridge extending transversely of the bristle face and .alongopposite sides thereof, portions of the said ridge on opposite sides ofthe bristle face Lying in a plane that slopes toward the base of thebru'shheadin the direction ofthehandie,thesaidridgeextending fromthefreeend of the brush-head, and these-id portions oftheridgeinthesaidplanebeingadjacentthe said free end: and bristlesplaced inwardly and outwardly from the rid e and forming slopingportions of the bristle face thatinclin'e toward the base of the brush.I

8.Inatooth brushcomprising-abrushheadlo including a base and;bristiesextending in substantiallythesamedirectionfromthebaseand forming abristle face, the free ends of bristles adjacent the free end of thebrush head forming a depressionin thebristiefacathesaid a,o4a,a9s

face and from substantially the said free end of the brush head, wherebya ridge is formed in thebristle face along the said sides of the bristleface and transversely adjacent the said free end of the brush head.

JAMEs A. MALCOLM.

